(1) Field of the Invention
This invention relates generally to communications and, more particularly, to packet communications systems.
(2) Background Art
CDMA (carrier division multiple access) packet data service represents one method of providing wireless data services to mobile users over Internet Protocol (IP) based networks (e.g., see Tom Hiller, xe2x80x9cWireless IP Network Architecture based on IETF Protocolsxe2x80x9d, TR45.6-3G/99.05.17.06). In TR 45.6, the point-to-point protocol (PPP) is used as the link layer between a mobile terminal, or mobile node (MN) and a Packet Data Serving Node (PDSN).
It has been proposed to enhance PPP to provide quality of service (QoS) features. One proposal is xe2x80x9creal-time framingxe2x80x9d (e.g., see C. Bormann, xe2x80x9cPPP in a real-time oriented HDLC-like framingxe2x80x9d, work in progress, (draft-ietf-issll-isslow-rtf-05.txt), April 1999). Another approach is xe2x80x9cmulticlass multilink PPPxe2x80x9d xe2x80x9c(e.g., see C. Bormann, xe2x80x9cThe Multiclass Extension to Multilink PPPxe2x80x9d, work in progress, (draft-ietf-issll-isslow-mcml-06.txt), June 1999).
Unfortunately, both these modifications are not well-suited to wireless access networks. For example, real-time framing is not, sufficient because the PPP peers are only aware of any different classes of service when bearer traffic appears on the receiving interface. However, for a wireless access network this information is needed to decide which type of wireless link to activatexe2x80x94before bearer traffic appears. With respect to multiclass multilink PPP, this approach fragments each packet for transport across multiple links. In addition, multiclass multilink PPP, while specifying the maximum number of classes for a multilink PPP session, does not specify the class definitions.
Multilink PPP is enhanced to provide for a more flexible quality of service (QoS) support in a wireless environment. In particular, and in accordance with the invention, multilink PPP is enhanced to enable a packet interface, or packet endpoint, to transmit a message to an opposite PPP peer, where the message identifies the number, and type, of classes on a particular PPP link.
In an embodiment of the invention, multilink PPP is modified to support a xe2x80x9cnon-Sharing QoS Negotiationxe2x80x9d option message, and a xe2x80x9cQoS-Enhanced Multilink Header Formatxe2x80x9d option message during the IP control protocol (IPCP) phase.